flopscope.

flopscope.numpy.union1d

Find the union of two arrays.

Adapted from NumPy docs np.union1d

Areacore
Typecustom
NumPy Refnp.union1d
Cost
per-operation
Flopscope Context

Set union; cost = (n+m)*ceil(log2(n+m)).

Return the unique, sorted array of values that are in either of the two input arrays.

Parameters

ar1, ar2:array_like

Input arrays. They are flattened if they are not already 1D.

Returns

union1d:ndarray

Unique, sorted union of the input arrays.

Examples

>>> import flopscope.numpy as fnp
>>> flops.union1d([-1, 0, 1], [-2, 0, 2])
array([-2, -1,  0,  1,  2])

To find the union of more than two arrays, use functools.reduce:

>>> from functools import reduce
>>> reduce(flops.union1d, ([1, 3, 4, 3], [3, 1, 2, 1], [6, 3, 4, 2]))
array([1, 2, 3, 4, 6])